Mortara Surveyor S4, Service Manual, Page: 62 / 67

56
TROUBLESHOOTING
Pulse oximetry (SpO
2
)
Symptom Possible causes Suggested remedies
Signal Quality
Indicator is
yellow;SpO
2
values continue to
be shown.
The physiological signal
sensed by the SpO
2
sensor is weak
Check patient status. Consider dark skin pigmentation, low
perfusion, venous pulsation, dysfunctional hemoglobins as
potential factors.
Remove nail polish from sensor site.
Confirm the fit of the sensor at the measurement site
– not too
loose, nor too tight that circulation may be affected in the
extremity.
Try alternate measurement sites.
Intermittent Circulation is being cutoff
Select an alternate measurement site for NIBP or SpO
2
.
dropouts of pleth at the SpO
2
measurement
waveform and which is distal to a NIBP
SpO
2
values cuff
Inaccurate values Interfering substances in
the patient’s bloodstream Check the patient condition for carboxyhemoglobin,
methemoglobin, intravascular dyes, or similar.
Physiological conditions Check the patient condition for cardiac arrest, hypotension,
shock, severe vasoconstriction, severe anemia, hypothermia,
venous pulsations, ventral septal defects, extremes in
systemic vascular resistance, or similar.
Cannot obtain
SpO
2
reading
The signal sensed by the
SpO
2
sensor is so weak
that it is not recognized as
physiological
Refer the row further above for possible ways to improve
signal strength.
Excessive artifact on the
sensor signal makes it
impossible to calculate
SpO
2
Refer the row below describing “’Artifact’ status message”.
No signal is being received
from the sensor
Refer to the row further below describing “Pleth waveform is a
square wave”
Electromagnetic
interference from external
equipment Do not use the S4 with electrosurgery equipment.
Check the immediate area of the S4 for other electronic
equipment. Increase the separation distance between them.
Consider discontinuing their use if not needed for patient
care.